The investigators will compare cortical bone tissue material properties, as assessed by novel in vivo indentation at the mid-tibia in postmenopausal women with recent hip fractures (n) and age-similar controls without fractures (n=). In addition to in vivo indentation measurements, The investigators will assess hip and spine BMD by DXA; as well as other factors that may influence risk of fractures (e.g, vit D status, medication use and physical activity). Hypotheses: Postmenopausal women with hip fractures will have worse bone tissue material properties compared to non-fracture controls even after adjustment for BMD and other potential confounders.